Dimmer



J. GALAMB AND E. P. OSWALD.

DIMMER.

APPLICATION FILED MAY 20, 1918- Patented Dec. 20, 1921.

l. GALAMB AND E. P. OSWALD.

DIMMER. APPLICATION FILED MAY 20, I918.

1,400,81 1 Patented Dec. 20, 1921.

2 SHEETS-SHEET 2- H d 3222 Liam out a w H Dimm iiinlhghfg Dimmed I Z4 31mm figswald.

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JOSEPH'GALAMB AND EARL P. OSW'ALD,

MOTOR COMPANY, Q1 DETROIT,"

OF.I)ETROI'I, MICHIGAN, ASSIGNORS TO FORD MICHIGAN, A CORPORATION OF MICHIGAN.

DIMMER.

Application filed May 20,

T0 all whom it may concern:

Be it known that we, Josnrrr GALAMB and which do not overloadzthe generator andithat efiects its, purpose even: when one of I the lights'of .the circuit or moreLthan one, are accidentally cut out. through being-burnt out or the like.

This invention relatestoa dimmer for automobiles having an A; C. generator, whereby an impedance is afl orded which-cuts down the effective current passing through the lamp, without overloadi or increasing the load of the generator an which also takes care of any lamps-on the circuit if others are accidentally burnt out or destroyed.

The invention consists in thematters hereinafter set forth, and more particularly pointed out in the appendediclalms.

In the drawings, v Figure 1 is a plan View partially broken away and in section, of'a device embodying features of the invention; j

Fig. 2 is a view, part-iallyinelevationand partially in section, taken at right angle to the view in Fig. 1,; p

Fig. 3 is a view in detail of laminations forming a coil core; Fig. 1 is a plan view of the laminations Fig. 5 is'a view in detail of a clip for retaining the laminations, and applied coils; Fig. 6 is a clamp cooperating with the clip to maintain the laminations and coils in proper relation;

Fig. 7 isa diagrammatic View showing the connections when the automobile lights: are bright; I

Fig. 8 is a diagrammatic view showing the lack of effect of the burning. out of one of the lights; and

Fig. 9 is a diagrammatic view showingthe light circuits with the vdimmer in operation.

Referring to the drawings, a coil coreis built up of sheets or laminations of magnetic material, each lamination consisting of Specification of Letters Patent.

' direction through the line, including windings 21 Patented Dec. 20, 1921.

1918. Serial No. 235,701.

a section 1 and a section 2 which when in contact on the medial line 3 thereof provide core apertures 1, therethrough because of registering notches or gains on the line of division, there being-lugs 5 and 6 on the endsof the sections for holding the outer portions of the coils. While the line of cleavage of the two sections, as indicated at 3, is medial, it is off center and the stack as indicated in F ig; 3, is formed by assembling the units in reverse alternate overlapping relations, around a central choke coil or winding-.7, anouter-circuit coil or winding 8 at onewend andacompanion circuit coil or winding 9 at the other. \Vhen so assembled, the stack is slipped intoa holder or clip 10 whichis in theform of a channel bar or thelike bent to have a pair of end arms 11 and 12 at right angles to the middle portion, so that the assembled coils and laminations may be readily dropped into place therein, the lugs'5 and Gwhich retain the coils carrying the windings S and 9, also holding the laminations and coils centrally in the member 10. A member 13 is secured upon the member 10 by bolts or the like passing through slots 14 at the ends thereof, and

corresponding slots 15 in outturned lugs 16 of the member 10, the whole being incased if desired.

The circuit coil or winding 8 is reversely wound to the circuit coil or winding 9 so that themagnetic flux through. the laminations produced by winding activity is in the same central leg of the core- Thesecircuit windings are connected in parallel through aswitch 17 with an alternating current generator 18 which is grounded and are severally in series with the headlights 19 and 20 as indicated. A few turns 21 and 22 of a'separate winding carried by the outer legs of the c'orewhich legsalso carry windings 8 and 9are in series with a tail light 23. As the candle power requirements of the tail light are-materially less than those of the headlights, the tail light and 22, is of high resistance value-indicated by the light linesin'Figs. 7 to 9, inclusive.

As a result, whenthe switch is turned as indicated in Fig. '7, the headlights 19 and 20 and the tail lights 23 are energized by a currentwhich is impeded only to a slight extent through the windings 8 and 9 by the magnetic flow set up through the laminations of the core. If one of the lights, as for example 20 (indicatedin Fig. 8) burns out or is thrown out of circuit, tending to increase the amount of current on the active lamps due to the drooping volt-ampere characteristic of the generator, the other light 19 is not seriously afi'ected as increase of current through the companion winding 9, causes an increase in the magnetic flux of the field with consequent increased impedance and lessened flow to the lamp.

The central choke coil 7 is connected in series parallel with the lamps 19 and 20 as indicated in Fig. 9 when the switch 16 is drawn to the position shown in Fig. 9 on the terminal or switch point 24. As a consequence the current fiow through the choke coil 7 induces a magnetic flow through the central leg of the laminations, augmenting that produced by the windings 8 and 9, thereby increasing the counter E. M. F. efiect on such windings. Because of this and in consequence of the counter E. M. F. induced in coil 7 both lights are dimmed as indicated in Fig. 9 and the tail-light also is slightly afiected although magnetic inductance of the few turns in serieswith this light is so slight as to have little effeet on this circuit branch. If either light breaks down or is thrown out, when the impedance coil is in operation, the increase of current in the other lamp winding compensates by intensifying the magnetic flux produced by the windings, thus maintaining the impedance efiectand thereby protecting the remaining lamp from over-current.

In case both headlights are burned out or accidentally disconnected, the windings of the tail lamp circuit'operate to prevent any excess flow through that circuit by producingsufiicient magnetic flux as to set up the necessary impedance.

As a result a dimmer is obtained which is efiective when the lights are all in operation or cut out, without seriously changing the load in the generator.

The device is light, very compact and easily assembled and placed in the car circuit.

Obviously, changes in the details of con struction may be made without departing,

from the spirit 01": our invention and we do not care to limit ourselves to any particular form or arrangement or" parts excepting such as may be required by the claims.

What we claim is 1. In an automobile, the combination of an alternating current generator, lamps supplied thereby, coils each in series with a lama a ma netic field ener ized in common 3 &

by the coils to retard flow through the lat-.

ter, an impedance coil adapted to increase the magnetic flow through the fields of the lamp coils and means for throwing the impedance coil into series parallel with the other coils.

2. As a means for varying the candle power of lighting systems for motor vehicles, and wherein the headlightcandle power winding adapted. to be selectively introduced into said circuit in electrical advance of the individual lamp windings.

3. As a means for varying the candle power of lighting systems for motor vehicles and wherein the headlight candle power varies from that of the tail light, means for establishing a circuit with the two headlights in parallel with each other-and with the tail light, and an impedance coil having a core includingthree legs, two of said legs carrying a winding in a headlight and the tail light branch circuits, with the several headlight windings in. parallel, said third leg carrying a winding adapted to be selectively introduced into said circuit in electrical advance of the individual lamp windings, said additional winding being adapted to augment the intensity of the field and vary the candle power of active lamps.

4. As a means for varying the candle power of lighting systems for motor vehicles, and wherein the headlight candle power varies from that of the tail light, means for each carrying a winding inthe headlightand the tail light circuit with the several headlight windings in parallel and wound to produce a flux path extending through the third leg, said latter leg carrying a winding adapted to be selectively introduced intosaid circuit in electrical advance of the individual lamp wind ngs, said additional winding being wound to augment the intensity of the field produced by the headlight' windings. 1

5. In a lighting system for automobiles and in combination, a source of alternating current supply, lamps in series therewith, windingsfor and within "each lamp circuit, a magnetic field formation positioned relative to the windings to produce field activity by current flow within the circuits, the wind ings being wound to produce counter E. M.

F. effects during current activitypand an impedance coil carried by said formationand adapted to be made active at will, said impedance coil, when active, being operative on the field to augment the counter E. M. F. effect on the windings.

6. A system as in claim 5 characterized in that the field formation includes three substantially parallel core portions'with the lamp windings restricted in position to the two outer portions of the formation.

7. A system as in claim 5 characterized in that the field formation includes three substantially parallel core portions with the impedance coil carried by the intermediate portion.

8. A system as in claim 5 characterized in that the field formation includes substan tially parallel core portions, with one of the lamp circuits having windings on two of such portions, said latter portions also carrying the windings of two other lamp circuits with the winding of a circuit positioned on a single portion.

9. A system as in claim 5 characterized in that the field formation includes substantially parallel core portions, with one of the lamp circuits having windings on two of such portions, said latter portions also carrying the windings of two other lamp circuits with the winding of a circuit positioned on a single core portion, said single lamp circuit windings being in series.

In testimony whereof we afiiX our signatures in presence of two witnesses.

JOSEPH GALAMB. EARL P. OSWALD.

Witnesses:

WM. H. SMITH, JOHN C. HAVENS. 

